Resistance Is Futile!
Resistors are used in passive crossovers to drag down the
efficiency of all the drivers in a loudspeaker to the "the lowest common
denominator" i.e. the least efficient driver in the design dictates the
maximum overall efficiency of the finished speaker. All the power
amplifier is doing is heating up a bunch of resistors (as well as all the
capacitors & inductors) which in turn degrade the sound. How wasteful is
that?!
The capacitors and inductors used in all passive crossovers
destroy time and phase coherence. All capacitors and inductors are, by
definition and function, "frequency dependant energy storage devices".
They release different frequencies at different times! The last thing you
should ever do to a music signal is introduce time & phase distortion. The
human ear is highly sensitive to this and it is heard (and felt) as the
most offensive and unnatural form of distortion. (See The Prey document
for more details on this crucial subject)
Back in 2001 we built and tested a number of 1st , 2nd and
3rd order passive crossovers using the most sought after components with
all the right designer names. These external crossovers were housed in
beautiful wooden boxes lined with black hole sound deadening & ERS
screening material, solid core silver wire and solder free "cold weld"
crimp joints were used to connect everything up. They were big, ( over 1
cubic foot per channel!) heavy, cost a fortune (£1,200 retail) in labour
and materials, and sounded….like all really good passive crossovers, poor
imitations of real life music. They were still 10 times more expensive and
sounded way better than the usual passive efforts that get stuffed inside
the speaker to suffer the vibrations and stray magnetic fields of the drivers.
There had to be a better way.
In the vast majority of professional recording studios and
all live music events only active crossovers are used. The sound engineers
would laugh at you if you suggested using passive crossovers to play back
"real music"! So we tested and compared a range of professional and
domestic designs as well as our own circuit design and power supplies.
We found that a carefully designed & well built analogue
active crossover using good quality industrial grade components out
performed any passive crossover no matter how exotic the components.
We concluded that it was well worth the extra cost to
design & build an active crossover rather than suffer the gross
deficiencies of passive crossovers. These active analogue crossovers were
still limited to a choice of traditional non linear Butterworth or
Linkwitz Riley crossover designs. They were also restricted by shallow
slopes, typically 24dB or at a push 48dB slopes. By this time (late 2003)
digital signal processing was really advancing in leaps and bounds and the
prospect of true linear phase crossovers with 96dB per
octave slopes was getting closer. There were only a few true digital
crossovers available back then and the clear leader of the pack was DEQX
headed by the very talented Kim Ryrie who is also a genuinely nice guy. By
late 2004 we had learned a lot about the world of DSP and all our
experiences (good and bad!) confirmed we were on the right track. Winning
two "best in show" awards (Fidelity magazine from Norway and Six Moons)
in Sept 2004 at the London Hi Fi News show proved our Encore speakers with
our modified DEQX crossover was indeed very special.
The Conductor & End Game were conceived in summer 2005 when
we were carrying out the ultimate in pure listening tests. Running
the Prey head units full range with no DEQX or any crossover at all we
used a CEC belt drive transport with the digital output hard wired
into our (then prototype) DAC's and used naked Vishay resistors to give
passive control of the volume.
The power amp was a "one off" Class A solid state stereo
power amp designed and refined over the last 10 years. All equipment was
running from dedicated laboratory grade mains and wired throughout with
solid core silver cables.
We discovered that the Prey (with our silver wired Manger
drivers) have a level of Purity and natural life like sonics that went far
beyond any other speaker we had ever heard. We knew then that we had to
develop all our other electronics and cables up to this rarefied
level. All current Overkill Audio products have been developed and
refined to complement the unique time and phase coherent point
source characteristics of the Prey.
As soon as we put a crossover into the system, even in
Bypass mode with no EQ used, we could instantly hear it degrade the sound,
every single time on all types of music. We tested all sections and
discovered that the brilliance of the DEQX is its DSP chip containing the
algorithms. There were already several specialist digital engineers
offering a raft of modifications and upgrades to the DEQX.
The audio forums were buzzing with the potential of the
basic DEQX but no one could solve all the problems. We explored many
options but in the end it became clear that we required a totally new
design with our own analogue to digital converter, USB input, our own
power supplies, casework, connectors, wiring and resonance control.
So we started at ground zero and have spent two years blood
sweat and tears painstakingly listening to each and every circuit layout,
type of analogue to digital converter, power supply transformer and
components all the way down to individual resistors. The culmination of
all this is "The Conductor" The results are spectacular and we are
immensely proud of it as a stand alone one box solution to 3 boxes of
problems!
The sound quality is fabulous, it actually disappears
sonically and proves beyond any doubt that "digital done right" is in fact
as beautiful as the music it reproduces! The Conductor even allows ultra
high end vinyl front ends to deliver their full potential through our
exclusive analogue to digital converter and associated power supplies.
They are designed and implemented to exceed the very highest archive &
replay standards.
In addition our unique design for USB inputs takes direct
digital feeds from computers, i Pods & hard drives (or even better solid
state or flash drives!) resulting in an unmatched level of sonic purity.
Please remember that there is absolutely no one else on the
planet able to develop any electronics that can approach, never mind
match, our level of sonic purity and dynamics. I repeat
there is absolutely no one else on the planet able to do this.
Why I hear the sceptical voice ask! Because no one else has the Prey! Some
people may think they have heard the Manger drivers and know their
potential, but until you get rid of passive crossovers and timber cabinets
you can not even begin to understand their beauty. We enjoy when the
“extreme” DIY guys come for an audition to see how their creations compare
with our commercial systems and they always leave with a “wow I never
knew…!” Even Audio Physics Medea owners are amazed at the dynamics and
realism of our speakers.
The Prey is our secret weapon, it’s like the having of an
electron microscope when everyone else is using a magnifying glass!
Using the prey we have developed a range of matching time
coherent bass systems and electronic components that are totally unique.
That's why we are able to be totally confident and say that
without any doubt the Conductor (& optional external DAC The End Game) is
the best Digital processor / Pre amp / DAC in the world.
For obvious commercial reasons, we can not reveal details
about our choice of components, our circuit design and engineering
techniques. The case work has no visible fixings and is designed to be
impossible to open without the key (similar to the locks on Porsche alloy
wheels) and if the case is forced it will cause irreparable damage to the
internal wiring. In addition if a someone buys a unit to rip it open they
will find that all components are sanded clean with no ID and all the
boards and components are fully potted in a resonance control epoxy
compound. So basically no way to reverse engineer this baby!!
We have massively over engineered the components and all
voltage and heat limitations have a minimum of three times rating
so faultless operation and total reliability is built in with peace of
mind. There are no valves or user serviceable parts in the design and all
units are covered with our back to base 3 year guarantee. All units (and
indeed all Overkill speakers and electronics) have a micro chip identity
device imbedded in them. This chip contains the “service history” of the
unit and can only be read or updated by using one of our hand held reader
/ scanner devices. This security device helps reduce insurance costs,
enhances resale value, discourages would be thieves and eliminates the
threat of buying a cheap Chinese fake. All using the same equipment as
vets do to micro chip pet cats & dogs! Another great idea from Overkill
Audio…!
Product Dimensions;
(W) 445mm (H) 150mm (D )400mm
Weight 16Kg (Shipping 22Kg)
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